Reverse Micelle Templated Construction of Strongly Confined Ultra‐Small Perovskite Quantum Dots with Exceptionally Narrow Blue Emission

Strongly confined quantum dots (QDs) have the advantages of a narrow full width at half maximum (FWHM) and rapid radiative recombination, making them promising candidates for realizing high-end display devices with exceptional color purity. However, the synthesis of stable and ultra-small perovskite QDs (UsPQDs) with a uniform size remains a critical challenge because of the difficulty of controlling picosecond ionic metathesis reactions. In this study, a novel reverse micelle soft-template strategy is demonstrated for achieving the precise nanoconfinement of CsPbBr₃ UsPQDs, yielding ultra-small monodisperse particles with an average diameter of 2 nm. The obtained CsPbBr₃ UsPQDs exhibited deep-blue emission at 443 nm and a narrow FWHM of less than 10 nm, accompanied by a near-unity photoluminescence quantum yield. The scalability and universality of this reverse micelle soft-template methodology are demonstrated, realizing the controllable synthesis of MAPbBr₃ and FAPbBr₃ UsPQDs with narrow blue emissions. A liquid-state light-emitting diode fabricated using the UsPQDs exhibited deep blue emission (CIE: 0.157, 0.018). A patterned dot-matrix display of 50-µm pixels fabricated via aerosol jet printing and photolithography demonstrated the viability of achieving wide-gamut augmented reality/virtual reality microdisplays.